Hey, TubeNube - how is your ST-70 project going?

Just wondering: By this time you should be fairly close to firing 'er up!

-- JunkyJan

Heh heh,

'Jan, your timing is impeccable.

I had the ST 70 finished last week, but was delayed by the pre-amp.

Following Bob's recommendation, I ordered a Transcendent Sound grounded grid pre-amp kit, and finished building it just last night.

But back to the ST 70 for a moment...

I was a tad nervous after finishing it, as I caught myself having made 4 or 5 dyslexic-type errors. I kept worrying there might be a 6th in there somewhere. I'm glad G_d invented fuses!

Anyhow, last night. Finished the pre-amp, hooked it all up. All includes a Squeezebox to stream lossless digital music from my computer and played through a Monica3 DAC, and out through a pair of Linn bookshelf speakers (they're the next to go!).

The Dynaco and Transcendent tube gear replaces a Naim integrated amp I've had for 17 years.

The sound? Wonderful. I was listening particularly closely to Ricky Lee Jones' Naked Songs, and noticed a fuller sound, with certainly more bass. There was a ... gentleness, or softness to the sound, which I believe to be a characteristic of tubes, yet there was definitely more detail than the Naim. I was sure I was hearing things I hadn't heard before, and ... I'm not just hearing things. ;-) It seemed to me that some of her guitar chords had additional notes/strings in there I hadn't noticed before. I'm sure of it because I was surprised by the additional notes in there.

I noticed a similar thing with the vocals. It might be fun to get out the old amp, and try to run a side by side comparison, just out of curiosity, but I really think it's too much effort.

One thing about the Naim ... well, two things. I always like its clarity, and it's punchy sound. It's been a great amp, and it'll serve my son well next year when he's off to college (lucky kid!), but compared to the tube gear, I now feel there's a harshness or edginess in the Naim.

Ok, so that's just a first blush. Clearly, I need time to get intimate with the new gear.

But I do want to add a couple of conclusions that are already obvious, and I can offer them without fear of contradiction.

This Dynaco amp is a phenomenal value for money. It's a great looking piece. Dynaco is a legend, yet this thing is a modern anachronism. It just tickles me to death that a 50 year old design has been able to be modified and upgraded so that it can sound so good.

The instructions were clear and easy to follow. The mistakes were all my own reckless fault for working too late in the evening after I was tired, combined with my natural tendency not to read things carefully enough but instead to say "yeah, I've got it" when I actually don't. Undoing mistakes was a cinch.

I haven't touched a soldering iron since the 80's. I think anyone who can learn to tie their own shoelaces can build this amp, learn a few valuable, transferable lessons, and save themselves a pile of dough considering what they have at the end.

Thanks for asking.

Brenton

Hi TubeNube

Congratulations - that is absolutely GREAT news! And BTW, I managed to blow a couple of fuses on first switch-on myself, too - it seems to be all part of the learning experience! Also... the fact that you managed to trace & fix the issues yourself, is a good indication that yo should be able to maintain this amp right into your old age ;-)

I had the same experience - I was totally blown away by the sound. I also own a couple of SET amps (actually used to - my university student son "stole" one from me) and I expected the modded ST-70 to be "nice" sounding, but not as detailed as the SET amps... I was wrong, it does have a slightly different sound but it is every bit as detailed.

I have a sneaky suspicion that many modern push-pull amps selling for many many $$$ are actually based on designs that are very similar to the ST-70 (if you think about it - how many different ways can a push-pull ultralinear amplifier work? Perhaps some detail differences etc...)

This amp has changed my whole outlook on High-Fidelity and the Audiophile industry in general. It made me realize just how much hype is out there - and how uninformed or just plain gullible some of us can be.

BTW, I am green with jealousy about your pre-amp - I am still running the NAD 114, and not happy with it at all (tendency to slight sibilance on female vocals, totally absent when I drive my ST-70 directly from my CD player). That is my next big change...

-- JunkyJan

Hey, J-J,

Maybe I'd realize how lucky I am if I actually had experience with other pre amplifiers, but I don't.

Once I got the Dynaco built, I ran my DAC straight to it, and didn't enjoy the experience. There was a sound as if air was leaking... not really a hissssss, or any kind of buss or hum. Then, I rationalized (perhaps correctly) that the impedance and the signal level are probably both wrong coming out of the DAC.

I also worried that maybe my 6th, undetected construction error was responsible.

But, once everything was in it's proper place, no noise. It's very quiet.

It's a shame about that sibilance you're getting.

I know money doesn't grow on trees, but that Transcendent amp is pretty cheap. Just think, though, how much cheaper it was just a few months ago when our dollar was worth more than the US dollar.

I think you are right about the ability (and courage) to maintain my own amp for years to come.

Also, all of a sudden, I don't be shy about soldering up what I think to be a loose connection in my DAC, if it materializes again.

Hey, did you find your amp "broke in" over time? I keep hearing about this, but don't know what exactly to expect.

-TubeNube

Geez,

Now that I'm talking and thinking about my stereo, I feel like leaving work early so I can listen to it!

(am I 15 again, or what?)

Bob, you're substantially responsible for this!!!

;-)

Tube Nube wrote:
....It's a shame about that sibilance you're getting....

Hi TubeNube

Totally traceable to the pre-amp (NAD 114). It is considered by some people in the Solid State Universe as a very good pre-amp, I guess those who haven't yet listened to a good tube preamp ;-) But, having said that, I am talking about the sibilance being noticeable by me only on some VERY challenging material - and on top of it, I have been blessed by the Maker with really good ears (flat frequency response measured every 2nd year when I undergo an Aviation - related medical exam).

Tube Nube wrote:
Hey, did you find your amp "broke in" over time? I keep hearing about this, but don't know what exactly to expect.

It seems to me that paper-in-oil caps (used as coupling caps on the VTA board, if you bought the cap upgrade) have a tendency to change its "sound signature" sligtly after running for some amount of time. I found that after about 70 hours, especially violin in classical concertos and alt sax on Jazz music started to sound like there is a "liquid" quality to it. My apology for the subjective observation (I hate audiophile magazines with all these kinds of idiomatic superlatives), but I can't think of a different way to describe it. I have heard / read somewhere that it is a typical characterstic of PIO type caps. Anyway, this "liquid" quality is HIGHLY pleasing while still being detailed as ever.

Interestingly, if you think that those EAT KT-88 tubes are expensive... Well you can easily spend more than that on "magic" coupling caps (yes, there are some brand names that sells for $400 or more for a .22 uF capacitor - and you need 4 of them... And it WILL influence your sound quality. That is one reason why I say there are better ways to improve your sound rather than spending $2000 on interconnect cable)

BTW, if you're into Jazz music, try find CDs from a recording company called "Mapleshade Studios". Their recordings are ABSOLUTELY amazing - and sounds incredible on the ST-70. If you ever wanted to demonstrate 3D depth in music using only 2 speakers, those recordings are perfect. Expensive though - out here in Vancouver you can expect to pay $30 - $70 per CD, depending on the subject matter. (Get if from Amazon, rather)....

-- JunkyJan

Jan,

You're pretty funny. I'm with you on the liquid -- I realized I was starting to sound, in my first reply to you above, like I was afflicted with that strangely annoying speech disturbance... let's call it "audio-lalia."

It'd be funny to put an audio-connoiseur (sp?) in a cage match with a wine-maniac and see what happens...

I did go for the cap upgrade you mention, so I'll look forward to whatever that will continue to bring to my ears in the hours to come.

I've made a note of your Mapleshade recommendation.

Now, drifting perhaps off topic for a moment, Jan, did you say . . . aviation medical? To keep it topical, that is music to my... well, to my eyes!

I was supposed to do my first cross country on Wednesday, but chickened out -- but I'm getting close to that other big dream coming true!

I think you and I may have a few things to talk about!